Self-locking pin.



No. 733,994. PATENTED JULY 21, 1903.

LA FAYETTE PIERCE. I

\ SELF LOCKING PIN. Arrmculor rum) IAB. 27, mos.

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PATENT ()FFICE.

LA FAYETTE PIERCE, OF MOUNDVILLE, MISSOURI.

SELF- LOCKING PIN.

SPECIFICATION forming part of Letters Patent No. 733,994, dated July 21, 1903.

Application filed March 27, 1903- fierial No. 149,794. (No model.)

To all whom, it may concern:

Be it known that I, LA FAYETTE PIERCE, a citizen of the United States, residing at Moundville, in the county ofVernon and State of Missouri, have invented certain new and useful Improvements in Self-Locking Pins, of which the following is a specification.

My invention relates to improvements in self-locking pins; and my object isto provide a pin which may be readily applied to a clevis for securing the doubletree. therein or any other purpose for which a pin of this character may be employed.

A further object is to arrange the key that locks the pin in position in such'a manner that by proper manipulation of the key and the pin the latter may be readily inserted or withdrawn from the clevis.

The invention may be further said to consist in the novel arrangement and combination of parts hereinafter described, and pointed out in the claims.

In the accompanying drawings, Whichillustrate the invention, Figure 1 represents a side elevation of the pin partly in section and applied toa clevis and doubletree. Fig. 2 is a detail front elevation of the pin and the key. Fig. 3 is a detail side elevation of the pin, partly in section, showing the key arranged therein in an elevated position and flush with the surface of the pin ready for insertion in the clevis or other object. Fig. 4 is a detail perspective view of the key'forming one of the important features of the invention.

In the drawings, 1 indicates a clevis provided at its opposite ends with the customary apertures 2, and 3 indicates a doubletre'e pro vided with the usual pin-hole at.

5 indicates my improved self-locking pin, which consists of a cylindrical body portion 5 and an integral conical head 6. Extending from a point about midway between its opposite ends to a point near the lower terminal of the pin is a longitudinal groove 7, consisting of an upper horizontal wall 8, extending a suitable distance into the pin, straight parallel side walls 9, and an inner curved Wall 10, extending downwardly and outwardly from the inner end of wall 8 to the surface of the pin near its lower terminal.

11 indicates the locking-key, which consists of parallel side walls 12, that snugly fitward movement of the key by contacting with wall 8 of the groove, and when in such elevated position the lower end of the key is fiush with the surface of the pin, so the latter may be inserted or withdrawn from the apertures in the clevis. The key is loosely held in position in the'groove by a retaining-pin 16, extending transversely through the groove a suitable distance below wall 8 to permit the key to drop down, so that its lower portion will protrude from the groove and contact with the lower corner of aperture 2 by the time the under side of its head 15 contacts with the retaining-pin 16, as shown in Fig. 1. When in this position, it is impossible for pin 5 to become accidentally disengaged from the clevis by j olting or otherwise, as any-upward movement on its part brings the protruding lower end of the key in contact with the lower corner of aperture 2, which forces the key in contact with the inner wall of groove '7 and causes pin 5 to bind in the aperture. The pin, however, may be readily removed from the clevis by elevating the key until its lower end is flush with the surface of said pin,

.as shown in Fig. 3.

When inserting pin 5 in the clevis and doubletree, it sometimes occurs where aperture 4 has been worn to unusual size that the key will drop down until its lower end contacts with the upper surface of the lower portion of the clevis and prevent the pin from entering the lower aperture 2. As the doubletree prevents access to the key, it becomes necessary to work the pin up and down rapidly until the key has been thrown upwardly in the groove far enough to permit the lower end of the pin to enter the aperture.

While I have described the pin as being used in connection with a clevis, it of course is understood that it may bereadily employed for a great many other purposes and frequently take the place of an ordinary bolt and nut.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

Ice

1. A pin provided with a longitudinal groove, a key having longitudinal movement therein, and means extending through the groove for limiting the longitudinal movement of the key.

2. A pin provided with a longitudinal groove, a key having longitudinal movement in said groove, and a transverse pin extending through the groove to limit the longitudinal movement of the key.

3. A pin provided with a groove having an inclined wall extending from a suitable point within the pin to its outer surface, a key having longitudinal movement in the groove and adapted to fit snugly against the inclined wall of the latter, a head formed integral with the key, and a transverse pin adapted to engage said head and retain the key in the groove, substantially as described.

4. A pin having a cylindrical body, an integral head, and a longitudinal groove, the latter comprising parallel side walls, a horizontal upper wall and a curved wall extending downwardly and outwardly from the inner end of the horizontal wall to the outer surface of the pin, a key having longitudinal movement in the groove and consisting of parallel side walls, curved parallel front and rear walls, a pointed lower terminal, and an outwardly-extending integral head; and a transverse pin extending through the groove and adapted to limit the downward movement of the key, substantially as described.

In testimony whereof I afiix my signature in the presence of two witnesses.

LA FAYETTE PIERCE.

Witnesses:

J. E. JONES, L. W. FRANKS. 

